Vertigo of cerebrovascular origin proven by CT scan or MRI: pitfalls in clinical differentiation from vertigo of aural origin.

To get a better insight into the clinical differentiation between vertigo of cerebrovascular origin and of aural origin, we investigated radiologically proven stroke patients who presented with vertigo as an initial clinical manifestation. Of 154 stroke patients, 30 patients with vertigo (20%) had the relevant lesion, demonstrated with the initial computerized tomographic scan (13 patients) or the follow-up magnetic resonance imaging (MRI) study (17 patients) of the brain. Every lesion was in the vertebrobasilar arterial territory; 19 in the cerebellum, 8 in the pons, and 3 in the medulla oblongata. Although 12 of the 30 patients (40%) presented with vertigo in isolation at the onset of stroke, eight patients (27%) developed additional neurologic abnormalities from four hours to seven days later. Patients with isolated vertigo (13%) had the small lesion exclusively in the cerebellum of the PICA medial branch territory. The most frequent accompanying neurological sign was swaying in the cerebellar and medullary lesion, and dysarthria in the pontine lesion. The direction of nystagmus or swaying did not match the lesion side in some patients. Our findings suggest that cerebellar stroke may commonly manifest isolated vertigo or vertigo with swaying mimicking labyrinthine disorder, particularly at the onset of the disease. MRI study and tests for truncal ataxia and lateropulsion may be crucial for the detection of vertigo of cerebrovascular origin.